Though Robert Carlock and Tina Fey have been writing partners for nearly 10 years now, collaborating on 30 Rock and Unbreakable Kimmy Schmidt, Carlock wrote Fey's new film Whiskey Tango Foxtrot on his own. "When we're doing TV, which is where the more official partnership is, it's often a question of agreeing on what we're doing and dividing the labor. But I think she knew this was an area I was interested in and that I would kill myself to try to get it right and that it was probably something that didn't demand another voice," he tells Co.Create.

Carlock's screenplay for Whiskey Tango Foxtrot is based on Kim Barker's memoir, The Taliban Shuffle: Strange Days in Afghanistan and Pakistan, and the film casts Fey in the role a cable news producer who decides to leave her safe but monotonous existence in New York City to go to Afghanistan to work as a television reporter.

As restrictive and dangerous as the environment in Kabul is, Barker thrives, throwing herself into her work and the underground party scene, too. She also fends off the amorous advances of an Afghan official (Albert Molina) and tumbles into a romance with a Scottish journalist (Martin Freeman). By the end of the film, Barker has become a more daring—and fulfilled—iteration of herself.

The Taliban Shuffle: Strange Days in Afghanistan and Pakistan

The role was a challenging one for Fey, calling on her skills as a comedic actress as well as her ability to do drama, especially in scenes involving a young soldier she believes was put in harm's way because of her reporting. "What was fun for me was knowing that this would stretch her in various ways," Carlock says. "We all know that she can do comedy, and we've seen her do the other stuff as well but in a much more comic framework. I knew I would be asking her to do stuff that she hadn’t really done before."

That said, Carlock considers Whiskey Tango Foxtrot a comedy first. "One of the great things was that as many people rolled their eyes as I was telling them I was writing what boiled down to an Afghanistan comedy, whenever I'd get on the phone with people who had been there [while I was doing research], they all—with varying degrees of enthusiasm, men and women—would say, 'Oh, I have so many funny stories to tell you,'" Carlock says. "Some of them were sort of horrifying, but I understood how they were comic—darkly comic."

While Carlock found Barker's book full of rich details and characters and both funny and sobering anecdotes, it took a lot of work for him to adapt Barker's story for the screen. "As memoirs tend to be, there was not a clear A to Z movie," he says. "It's an emotional journey she goes on over the course of the book and to make that cinematic was a tricky thing."

Evan Jonigkeit and Tina Fey in Whiskey Tango Foxtrot

Barker, who had sold the rights to her story, was well aware that part of the deal was allowing her story to be reinterpreted, according to Carlock. "She was very generous about, 'Yeah, you bought my life, and now you guys got to do with it what you will,'" he says. "I think one of the first things she said was, 'You're cutting Pakistan, right?' Half her book, or almost half, was her life in Pakistan, and I said, 'Yeah, I think I've got to cut that. It's a whole other story. Afghanistan is the film story.' "

Beyond reading Barker's book, Carlock researched life in Kabul and interviewed other reporters who had spent time there, members of the military and people who had worked for NGOs (nongovernment organizations) before he started writing the script for Whiskey Tango Foxtrot. "I knew I had to know enough about this world and then do my version of it," he says, noting, "At one point Kim actually said, 'I think you're over-reporting this. You need to start writing!' That was really freeing. It was a helpful spur."

Carlock used his research and reporting to add new scenes that aren't in the book, including an interaction between Fey's Kim and a U.S. Marine Corps General (Billy Bob Thornton) that earns her his respect and another that has Kim going undercover in a burqa and getting herself into a dangerous situation. He also made the film's heroine a television journalist (the real Barker was a print journalist), and he created an aggressive foreign correspondent (Margot Robbie) who is a friend/foil for Barker.

"I'm sure there is a movie that could have hewn much closer to the book," Carlock says. But he did stay true to the real-life Barker's core experiences, depicting in detail, for example, the friendship she developed with her fixer, who is known as Fahim (Christopher Abbott) in Whiskey Tango Foxtrot.

A former doctor who worked as Barker's guide and translator, he also enlightened Barker regarding local customs and culture during her time in Afghanistan and served as a fierce protector. The depiction of their relationship on-screen is complex and sweet. "To me, that is the core relationship of the movie," Carlock says.

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